1. Field of the Invention
The present invention relates generally to medical methods and apparatus. More particularly, the present invention relates to the design and use of energy delivering probes for thermally coagulating and/or constricting hollow anatomical structures (HAS) including blood vessels such as the perforator veins which connect the superficial veins to the deep veins in the leg, truncal superficial veins of the leg (e.g., great saphenous vein, short saphenous vein, and the like), superficial tributary veins of the leg, internal spermatic veins (varicoceles), ovarian veins, gonadal veins, hemorrhoidal vessels, fallopian tubes, a-v malformations, a-v fistula side branches, esophageal varices, and the like. Additionally, the probes may be used for thermally coagulating tissue, such as cancerous breast or liver tissue. For purposes of illustration, apparatus and methods of the present invention for use in treating perforator veins will typically be described.
2. Description of the Related Art
Perforator veins connect the deep venous system of a leg to the surface veins which lie closer to the skin. Normal or healthy perforator veins pass blood from the surface veins to the deep veins as part of the normal blood circulation. Incompetent perforator veins allow blood flow from the deep venous system to the surface veins, causing or contributing to problems, such as varicose veins, edema, skin and soft tissue changes, lipodermatosclerosis, chronic cellulites, venous ulcers, and the like.
Several procedures have been proposed for interruption of incompetent perforator veins. The “Linton” procedure requires a very long incision (knee to ankle) on the medial calf to expose the perforator veins. Individual veins may then be surgically dissected, ligated, and cut to prevent blood flow between the superficial and deep venous systems. A less invasive alternative has been developed by DePalma where individual incompetent perforator veins are identified along “Linton's Line” using ultrasound. Small incisions are then used to access the individual perforators for ligation and dissection. More recently, individual ligation and dissection of perforator veins has been performed using an endoscope inserted in the proximal calf.
Although generally effective, each of the above-described procedures requires surgical incisions followed by ligation and cutting of the veins. Thus, even at best, the procedures are traumatic to the patient and require significant surgical time. Moreover, the procedures are complex and often require a second surgeon to assist in the procedure.
For these reasons, it would be desirable to provide additional and improved techniques for disrupting incompetent perforator veins for the treatment of varicose veins, edema, skin and soft tissue changes, lipodermatosclerosis, chronic cellulites, venous ulcers, venous ulcers, and other conditions. Such procedures should preferably be minimally invasive, e.g., relying on an introducer sheath, cannula, catheter, trocar, or needle for gaining access to the perforator veins at the deep fascial plane. In particular, it would be desirable if the methods required few or no incisions, could be performed under a local anesthetic, would reduce post-operative healing time, as well as morbidity and complication rates, and would require only a single surgeon. In addition, it would be desirable to provide apparatus and methods which are useful for performing procedures on other tissues and hollow anatomical structures in addition to perforator veins. At least some of these objectives will be met by the inventions described herein below.